1. Field of the Invention
The present invention relates to a composition of matter which provides anti-static and anti-brick properties when coated on a film surface. The present invention relates to film, and in particular microfilm, having coated thereon the anti-brick/anti-static composition.
2. Description of the Prior Art
The application of antistatic agents to prevent static buildup on film products is known as a general concept. The use of various specific materials to prevent bricking or blocking of films is also known to the art. For example, some of the most useful antistatic agents for use on film materials are the quaternary ammonium salts of N,N dimethyl, N-(2-hydroxyethyl) stearamidopropylamine. In particular, stearamidopropyldimethylhydroxyethyl ammonium nitrate has been used to prevent static buildup on film materials. A commercial grade of this material, Catanac SN, is manufactured by the American Cyanamid Company.
One of the disadvantages in using antistatic agents of this type, however, is their tendency to promote bricking or blocking of film surfaces. This is particularly true for films coated with diazo or vesicular microfilm emulsions.
The bricking or blocking of films containing antistatic agents may be reduced or prevented by applying small quantities of a lubricant or particulate spacing material to the surface of the films. The literature contains many references to the use of particulate materials such as silica, talc, and the like for use in preventing bricking.
The particle size of effective anti-bricking agents, however, has caused a problem in becoming visible during the viewing of the film. This is particularly true in the viewing of microfilm products, which generally are used over a wide range of magnification as well. Because of this visibility requirement, most anti-bricking materials have been unsatisfactory for use on microfilm products. Moreover, as the particle size of the anti-bricking agent is reduced, in an attempt to reduce its visibility, it becomes less effective as an anti-bricking agent as it loses its capacity to act as a "spacer" particle to separate the film surfaces.
Accordingly, it is an object of the present invention to provide a novel anti-brick/anti-static composition which is truly effective with regard to both properties.
Another object of the present invention is to provide an effective anti-brick/anti-static composition which exhibits good compatibility and stability.
Yet another object of the present invention is to provide an effective anti-brick/anti-static composition which does not result visibility problems upon viewing a film coated with the composition.
Another object of the present invention is to provide a film product, and in particular a microfilm product, having coated thereon such a novel anti-brick/anti-static composition.
Still another object of the present invention is to provide an effective anti-brick/anti-static composition which resists rub-off from a film surface during handling.
These and other objects, as well as the scope, nature and utilization of the invention, will be apparent to those skilled in the art from the following description and the appended claims.